1. Field of the Invention
The present invention relates to a nonvolatile memory and a semiconductor device including the nonvolatile memory.
2. Description of the Related Art
A memory element composing a nonvolatile memory has a low resistance state and a high resistance state. A memory element is called an anti-fuse type if a resistance is high in an initial state, and it is called a fuse type if the resistance is low in the initial state.
These nonvolatile memories are effective when they are mounted to tags that perform wireless communication (also called “RFID tag,” “wireless tag,” or the like), because they do not need power sources when holding data. In particular, a write-once memory has received attention as a memory with high security, because it cannot be erased once it is written in. Note that wireless tags can be largely classified into two types: an active-type incorporated with a power source (for example, a battery) for driving; and a passive-type that is driven by utilizing power of an electric wave or electromagnetic wave (carrier wave) from outside (refer to Patent Document 1: Japanese Published Patent Application No. 2005-316724 for the active-type, and to Patent Document 2: Japanese Translation of PCT International Application No. 2006-503376 for the passive-type).